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arXiv · 2201.04519

On the Seshadri constants of equivariant bundles over Bott-Samelson varieties and wonderful compactifications

Indranil Biswas·Krishna Hanumanthu·S. Senthamarai Kannan
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Abstract

We study torus-equivariant vector bundles $E$ on a complex projective variety $X$ which is either a Bott-Samelson-Demazure-Hansen variety or a wonderful compactification of a complex symmetric variety of minimal rank. We show that $E$ is nef (respectively, ample) if and only if its restriction to every torus--invariant curve in $X$ is nef (respectively, ample). We also compute the Seshadri constants $\varepsilon(E,x)$, where $x\, \in\, X$ is any point fixed by the action of a maximal torus.

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Indranil Biswas, Krishna Hanumanthu, S. Senthamarai Kannan. 2022-01-12. On the Seshadri constants of equivariant bundles over Bott-Samelson varieties and wonderful compactifications. https://arxiv.org/abs/2201.04519

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